1. Field of the Invention
The present invention relates to a storage battery suitable for a regenerative charging system used in, for example, an automobile, a motorcycle, an electric tram, an elevator or a windpower station.
2. Description of the Related Art
In recent years, vigorous research is being conducted on, for example, a hybrid automobile, a motorcycle, an electric tram, an elevator and a windpower plant each having a battery mounted therein in order to utilize effectively the energy, and to utilize effectively the regenerative energy in view of the preservation of the earth's environment. As a matter of fact, a lead-acid battery and a nickel-hydrogen battery have already been put to practical use in, for example, a hybrid automobile having a battery mounted therein.
However, the nickel-hydrogen battery used in, for example, a hybrid automobile, gives rise to the problem that heat is generated rapidly during the high output stage or in the rapid charging (regenerative) stage. In addition, the battery incurs very large thermal deterioration.
Such being the situation, mounting of a lithium ion battery having a thermal deterioration smaller than that of the nickel-hydrogen battery and capable of making the battery module lighter in weight and thinner is being studied. However, a serious problem remains unsolved in the lithium ion battery in that the battery is swollen so as to be deformed under a high temperature environment in, for example, the summer season.
Disclosed in Japanese Patent Disclosure (Kokai) No. 2003-219510 is a charge-discharge control device equipped with a charge-discharge power control means for controlling the charge-discharge power so as to prevent the charge-discharge power from exceeding a predetermined upper limit of the charge-discharge power that is changed in accordance with the temperature in the case where the temperature of the secondary battery exceeds a prescribed temperature.